Improvement in machines for cutting screw-threads on bolts



N4 PETRS. PHOTO-LITHOGRAPHER, WASHINGTON, D U.

HENRY MARTIN, OF LOUISVILLE, KENTUCKY.

IMPROVEMENIIN MACHINES FOR CUTTING SCREW-THREADS 0N BOLTS.

` Speciiication forming part of LettersPatent No. 112,612, dated March 14, 1871.

To all whom it may concern Be it known that I, HENRY MARTIN, of

p Louisville, in the county of Jefferson and State of Kentucky, haveinvented a new and Improved Machinefor Cutting Threads on Bolts;

and I do hereby declare that the following is a full,`clear,' and exact description thereof, reference being `hbil t0 the accompanying drawing, making part of this speciiication, in whichy Figure 1, Plate 1, is a front view of the improved machine, showing bolt-blanks applied to their holders, andthe several parts in position for` commencing the threadingoperation.

Fig. 2, Plate 1, is a top viewof the machine. Y Figs. 3 and 4, Plate 1, show the construction of the bolt-holders. "Fig 5, Plate 2, is an elevation of one side of the machine. Fig. 6, Plate 2, is a diametrical section through the right-and-left` clutching devices of the main spindle. Fig. 7, Plate 2, is` a section taken vertically through the top, bed, two of the taps or screw-plates, andthe oil-basins.

Similar letters of reference indicate corresponding parts in theseveral figures.

. n This inventionrelates to certain novel imi provements on machinery adapted for cutting threads on bolts.

It consists, first, ina bolt holding and centering device applied on the lower end of a vertically-movable spindle, which latter is arl ranged overa device for cutting screw-threads, y as will be hereinafter explained;` second, in one or more spindles, which carry bolt-holders on their lower ends, and which are vertically ad- Y justable independently of each other, andver- `tically movable collectively, whereby threads 4can be cut `on bolts of different lengths, or of `the same. length, as will be hereinafter explained; third, in a vertically-movable frame carrying a gang of spindles having bolt-holders i applied to their lower ends, which spindles are` all rotated simultaneously by means of gearwheels,the central 'oneof which is on a spindle which is hung from a lever having a counterbalancing-weight that will prevent the weight of said frame and spindles from pressing unduly on the threadswhile being cut, as will be hereinafter explained; fourth, in the combination of a rack, a hand-lever, and a connectingp 51:06; with the lever from, which the main drivagainst the spindle.

ing-spindle is hung, whereby the attendant can Velevate the gang of spindles and their frame and support the same in an elevated position, as will be hereinafter explained; fifth, in the combination of a tripping device with a right-and-left reversing-clutch, whereby the machine can be set for cutting threads of different lengths, and when any given length of thread is cut the said device will automatically reverse the motions of the spindles and withdraw the bolts from their tops or screwplates, vas will be hereinafter explained.

To enable others skilled in the art to understand my invention, I will -eXpla-in its construction and operation.

In the accompanying drawing, A represents a post, which is secured rigidly in an upright position. B B are two vertical guides for a horizontal vertically-movable frame, C, which carries spindles b b b b. This frame consists of two horizontal plates, connected together,

Vat a proper distance apart, by means 4of shouldered posts p, on the ends of which nuts are applied.

Between the two plates constituting frame are five spur-wheels, the central one, c, of which is keyed on the lower end of a vertical spindle, c', and t-he others, b', engage with this central wheel and are applied on the spindles b. Each spindle b is connected to its wheel b by means of a feather and groove, the latter being made' into the spindle, so as to allow the. spindle to vbe adjusted vertically.

Each-spindle b is held by means of two collars, c e, arranged above and below frame C, through which set-screws e pass and bear By loosening the setscrews e e spindle b can be adjusted up or down through the hub of wheel b', according to the length of the bolts which are to be threaded. By thus making the spindle b adjustable, independently of each other bolts of diierent lengths can be applied to the machine and threads cut on them at one and the same time.

On the lower end of each spindle Vb is a boltholder, consisting of a rectangular enlarge-- ment, S, which `is vertically and centrally slotted to receive a hand-lever, S1, which is acted upon by a spring,.s, and pivoted at s. To this lever S1 a vertically' adjustable head- -FFTGR holder, S2, is applied, and below this headholder is a chuck, P, which is secured into an oscillating bed or chuck-holder, N. The chuck P is adapted to receive the heads and angular shanks of the bolts; or, if desirable, the oscillating bed may receive the bolts directly, and when the holder N is held by the lever Sl and shoulders g g in the horizontal plane, (indicated by Figs. 3 and 4 in full lines,) the vertical axis of a bolt, B', in the chuck will coincide with the vertical axis of the spindle bf The chuck-holderNis connected to the lower ends of the enlargement S by means ot' trunnions t t, which, when the lower end ot' lever Sl is forced out, by grasping its upper end the said holder can be tilted forward, as indicated by dotted lines, Fig. 4, and the bolt B' readily removed or a bolt-blank introduced.

The spring s1, acting upon the upper arm of lever Sl, forces the lower notched end ot' this lever against the edge of the chuek-hohler when the latter is horizontal, and thus holds it in this posit-ion. At the same time it brings the head-holder S2 directly over the head of the bolt and keeps the latter down in place in its chuck F. rlhe opening through the chuck l? is adapted to the size and shape of the heads and shanks of the bolts to be threaded, and a set-screw, s2, is used to hold the chuck in place in the holder, and allowachuck to be removed and another to be introduced in its stead.

The notch o in the back part of the chuckholder N is intended to receive the end of the head-holder S2 when the parts are adjusted, as indicated in dotted lines, Fig. 4.

The spindle c passes up through two bellshaped bevel spur-wheels, F F, and through a double clutch, H,andis attached by a swivel to a stirrup, 7c, which latter is suspended from an arm, K, by means of an adjustable hooked rod, kl. The arm K projects from an oscillating bar, K1, which is supported by bearings k3 L, and to one end of this bar another arm, K2, is rigidly secured, which extends backward and has suspended from it a weight, W. The

weight W thus serves to counteract, in a measure, the weight of the frame C and its spindles, so that there will not be an undue weight upon the screw-threads while being cut. The weight of the frame C and its spindles should preponderate a little over the weight of XV.

The wheels F F are connected to 'brackets E E by means of collars ff, so that these wheels may turn freely, at times independently of the spindle c, which passes through their axes.

rlhe teeth on wheels F F are engaged by the teeth of a bevel-pinion, a2, which is on a horizontal driving-shaft, a, carrying also pulleys el; consequently, said wheels F F are rotated in opposite directions. Between the two bellshaped wheels F, and connected to spindle c .by a key-tenen and a groove, is a clutch, H, having teeth on opposite ends pitched in opposite directions. Inside ot' the wheels F F are clutch-teeth my, which correspond to the' teeth on the clutch H.

It will be seen that the spindle c can be caused to rotate either to the right or to the left by adjusting the clutch H so as to engage with one or the other; and it will also be seen that spindle c and the frame (l and spindles b can all move up or down, whether spindle c be rotating or not.

The arm K2 is connected by a rod, r, to a hand-lever, B', by vibrating which the frame C and its attachments can be moved up or down.

The rack B is used to hold down hand-lever B' when the frame C and its attachments are elevated, as shown in Fig. 1.

When lever B is disengaged from its rack B the said parts C b c' will descend by their own gravity.

By means of a band, i, and a yoke-arm, I, the clutch H can be moved up or down.

The arm I projects from a rock-shaft, g4, which is supported by bearin gs h h, and which carries on one end a lever, G. From the rear end of lever G a weight, V,is suspended, and to the front end of this lever a rod, g2, is pivoted. This rod g2 extends down and terminates in a handle, and between the handle and its upper end a stud, g1, is secured by a nut applied onits stem, which latter passes through a vertically-oblong slot. This allows the stud g1 to be adjusted up or down.

To the lower part of the guide B, nearest rod g2 a shelf, g3, is secured, having a knifeedge formed on its front edge for engaging with one or the other of two notches made into the edge ot' said rod g2. (Shown in Fig. 5.) The notches in rod g2 are so arranged relatively to the position ot' the clutch H and the wheels F Fthat when this rod is drawn down and its highest notch engaged with the knifeedge g3, the clutch H will be engaged withv the lower wheel F 5 and when the lower notch is engaged by the knife-edge g3 the clutch will not engage with either one of wheels F.

Vhen the rod g2 is released from the knifeedge g3 the weight W will throw up the clutch H and engage it with the upper wheel F.

N ow, in order to reverse the rotation of the spindles c b at any desired point during the descending stroke of these spindles and the frame C, I fasten to this frame C a beveled trip, g, and adjust the stud g1 so that at the moment the required length ot' thread is cut on the bolt the trip will disengage the rod g2 from its knife-edge g3 and allow weight W to move clutch H from the lower wheel F to the upper wheel F, thus unscrewing the bolts from their taps.

The taps or screw-plates X X are applied fast to a bed, M, which is surrounded by a ledge, A1, and which has secured beneath it a pan, V. The ledge A1 andpan V form a basin to contain oil for the taps or screw-plates and bolts during the process of threading.

The taps and tap-bed are arranged horizontally beneath the spindles b, and applied to a vertically-adjustable plate, A2, which is secured to post A.

It is obvious that` a machine with a single spindle and bolt-holder can be made by dispensing `with the spindles b b, their bolt- "holders, and the gearing for operating the spindles, andmakingthe shaft c to extend down below the guide-frame G, and applying a bolt-holder, such as described, upon its lower end, in the same manner that it is applied upon the spindle b. In this case the screw- `cutting die-bed would be tapped in its` center only, and the frame G would be connected to the shaft c by collars, which would insure a vertical movement, together with the frame and shaft, but permit an independent rotary movement of the shaft.

I, however, do not regard such an arrangement as useful and valuable as the plan represented,'as only one bolt can be threaded at a time by the modification suggested, whereas `four at a time can be threaded by theV plan represented in' the drawing.

Having thus described my machine and the manner of its operation, Inow claim nothing as newthereiu but the following:

1; In combination `with a rotating spindle of a bolt-threading machine, a bolt-holding `mechanism comprehending a stock integral ings, I?, as set forth.

3. Ihe bolt-holding` and centering device D, consisting of the slotted head S, the handlever S1,and its head-holder S2, in combination with a rocking holder, N, substantially as described. A

4. The frame G C, in combination with the `outside guides, B B, of the main frame A, shaft c', bolt-carrying spindles b, constructed and operating substantially as and for the purpose described. A 4

5. The weight W', oscillating arm K ,K2 union K1, and adjusting device R', in combivnation with the suspending and spindle-driving shaft c', and with the movable spindle and gear-supporting frame G, substantially as and for the purpose herein described.

6. In combination with one or more rotating and vertically-movable bolt-holding spindles, and one or more screw-threading dies fixed upon a permanent table, a clutching apparatus located on said spindle, by which the motion of rotation of the latter may be reversed, a lever and a catch, the former weighted at one end for holding the movable section of the clutch apparatus in contact ywith one of the stationary sections thereof, and a hook on the other end to engage with the catch when said central section of the clutch is brought in contact with the other stationary section, and a frame or other device integral with or attached to the spindle, the whole combination being such that the dies, in drawing the spindle toward them while cutting, shall force the frame to release the hook of the lever from the catch, and thus cause the reversal of the clutch apparatus and the reversal of the movement of rotation of the spindle.

7. The tripping device g, g', g, g, and c", applied as and for the purpose described in both threading-machines.

8. The loaded lever G, rock-shaft g4, clutcharm I, and rod g2,in. combination with knife- 'edge g3, tripping device g g', and the verticallymovable spindle-frame C, substantially as de scribed.

9. The combination of the tap-bed M, oilbasin A1 and V, gang of vertical spindles b, bolt-holders D, and vertically-movable frame G, substantially as described.

10. The machine, constructed as herein described, forA threading bolts and withdrawing them from their taps, and also adjusting them to an inclined position for ready removal, all as set forth.

HENRY MARTIN.'

Witnesses:

GHRrsrrAN BEST, ROBT. W. RAMsEY. 

